Paint-removing composition and process of making the same



Patented Mar. 24,

-WWW

'- su g it'o Drawing, Application filed may 29,

To all who/"wit vii-cg concern:

Be it known that l, LOGAN L. h/iALLARD, citizen of the United States, residing at- Norfolk, in the county of Norfolk and State of Virginia, have invented'certain new and useful Improvements in Pziint-Removing G'ompositions and Processes of Making the Same, of which the following is a specification.

This invention relates to compositions for removing paint from coated surfaces.

An important object of my invention is to provide a paint removing composition adapted to morereadily and completely remove paint than prior compositions intended for the same purpose.

Another object of my invention is to provide a paint removing composition adapted for removing paints, enamels, varnishes and the like, irrespective of the. composition of the coating material whereby a single composition is adapted for use in removing paints, enamels, varnishes and the like of any characten A further object of this invention is to provide a paint removing composition which is inexpensive to manufacture, not injurious to the skin and which iii-use, does not give oil fumes detrimental to health so that the composition may be satisfactorily'used indoors. i i

Heretofore aqueous solutions oi": alkali metal and alkaline earth metal hydroxide, and carbonates have been employed for the removal of paint,'either alone or in association with an organic-acid. or-an organic acid and a volatile solvent and such compositions have been found-to be quite satisfactory for removing certain commonly used paints, varnishes and" the like, particularly when applied in arheatedcondition, Now I have discovered that the efficiency of such compositions containing caustic alkali and an organic acid is materially improved by the addition to an aqueous solution con tainmg the same of calcium carbid. In

the use of calcium carhid in accordance with my invention it is added to an aqueous solution of caustic alkali and a suitable organic acid, either with or Without other materials 192753., Serial No. 6%2329.

and, when the resulting reaction is completed and the comp osition allowed to cool,

a volatile solvent may advantageously be added thereto. In the practice of in y inventio: in proper- 11g a paint removing composition of intensive activity for use on ordinary paints and varnishes such as is used on houses,

furniture, automobiles to employ sodium hyd ate, oxalic acid and boron,

proportions of 16 part hydroxid, 32 parts by and the like,

I prefer romd, sodium :arbonin the preferred s by'iveight or sodium Weight of sodium carcomic, 6 parts by Weight of oxalic acid and 10 parts by Weigh ture is dissolved in a dc t of boral'e The mixsired quantity of Water depending upon the strength of the solution to be obtained. 1 ordinarily dis-- solve the mixture in approximately 10 gab lons 0:1 Water. calcium carbid,

reaction is complete cooled to not abo ve bloc To this mixture I then add preferably using about 4: pounds of the cal-bid.

When the resulting; and the mixture has d temperature I add a volatile solvent preferably benzol or gasoline ordinarily making use of about four pounds of such solvent. then added a ulverized preferably starch or tions lis to make a th thinly applied on a To the mixture is starchy material, flour in such. proporick paste which when vertical surface will maintain its position thereon.

This composition. is

used by being applied in a' thin coating on the paint, varnish or the like to be removed and allowed to remain thereon until the paint is softened and ready for removal whereupon the paint and paint removin application of water,

sprayed thereon from a nozzle.

application of the pa ordinarily suliicient t g paste are removed together by the being A. single int removing 0 remove paint from preferably by any surface coated therewith.

The composition ab ove set forth is rapid with this composition.

in order to provide paste a composition which is adapted for use on any paints, enamels, varnishes and the like, 1 employ in addition to the materials hereinbc'fore mentioned, Epsom salts, sal-ammoniac, copper sulfate, alcohol, either wood alcohol or denatured alcohol, preferably the latter, and ethyl other. i

In making this composition I prefer to employ the materials in the following proportions:

Pounds. Sodium hydroxid; 16 Sodium carbonate 32 Oxalic acid 6 Borax 10 lalcium carbid 4 Epsom salts 1 Sal-annnoniac 2 Copper sulfate 4 Benzol or gasoline 4 Alcohol 4 Ethyl other 4 The benzol or gasoline, the alcohol and the other are not added to the composition until a l'ter a solution in water has been made, the calcium cal-bid added to the'solution as above, described and the resulting solution allowed to cool to not above blood heat. The. bcnxol or gasoline, the alcohol and the other are then added and the mixturc or solution thickened with the finely divided starchy material added thereto.

I have found it advantageous in the use ol starch or flour to first mix the same with a small amount of water to form a thick homogcncous paste free from lumps. This can advantageously be added to the mixture containing the other ingredients of my composition' while mechanically stirring the same.

The chemical effect of the addition of the calcium carbid is not understood. It has been found, however, that the elfect of the calcium carbid is different from that of calcium hydroxid and that the use of calcium carbid results in the production of a paint removing composition of superior quality and greater effectiveness.

In place of oxalic acid I have found that some measure of success may be obtained by the use of other organic acids, as for example, acetic acid and that the soluble salts of suchacids can be used. Similarly I have found that a considerable measure of success may be obtained by the substitution of trisodium phosphate tor the sal-ammoniac, These materials are therefore to be regarded as chemical equivalents in the practice 01 my invention.

\Vhile I prefer to employ a pulverized starchy material to' maintain my composi tion in contact with the paint to be removed, the composition with the starchy material omitted can be satisfactorily employed.

lVhile I have described in detail the preferred form of my invention and preferred proportions of materials used it will be understood that my invention is not limited to the particular proportions set forth nor to the details of procedure in the production of my improved paint removing composition.

Having described my invention, I claim:

1. The herein described paint removing composition comprising an aqueous solution of approximately 16 parts by weight of sodium hydroxid, 32 parts by weight of sodinm carbonate, 6 parts by wei ht of oxalic acid and 10 parts by weight 0 borax, and the products of the reaction of approximately 4 parts by weight of calcium carbid on the said solution, said solution having approximately 4 parts by weight of benzol mixed therewith, the mass bein thickened by a pulverized starchy materia 2. The herein described paint removing composition comprising an aqueous solution of sodium hydroxid, sodium carbonate, oxalic acid, borax Epsom salts, sal-ammoniac and copper sult ateand the products of the reaction of calcium carbid on the said solution.

3. The herein described paint removing composition comprisingan aqueous solution of approximately 16 parts of sodium hydroxid, 32 parts of sodium carbonate, 6 parts of oxalic acid, 10 parts of borax, 1 part of Epsom salts, 2 parts of sal-ammoniac, and 4 parts of copper sulfate, and the products of the reaction of approximately 4 parts by weight of calciumcarbid thereon, the resulting solution having mixed therewith approximately 4 parts of benzol, 4 parts of alcohol and 4 arts of ethyl other, the proportions being y weight.

4. The herein described paint removing composition comprising an aqueous solution of approximately 16 arts of sodium hydroxid 32 parts of sodium carbonate, 6 parts of oxalic acid, 10 parts of borax, 1 part of Epsom salts, 2 parts of sal-ammoniac, and 4 parts of copper sulfate, and the products of the reaction of approximately 4 parts by weight of calcium carbid thereon, the resulting solution having mixed therewith approximatel 4 parts of benzol, 4 parts of alcohol an 4 parts of ethyl ether, the proportions being by weight, the mass bein thickened by a pulverized starchy matcria 5. The herein described process of making a paint. removing composition comprising dissolving in Water a caustic alkali and a suitable organic acid and adding calcium carbid thereto.

G. The herein described process of making a paint removing composition comprising dissol in in water sodium hydroxid, sodium car onate and oxalic acid and adding calcium carbid thereto.

7. The herein described process of making, a paint removing composition comprising dissolving in water sodium hydroxid, so

10 9. The herein described process of making ,a paint removing composition comprising dissolvin in water-sodium hydroxid, sodium car onate and oxalic acid, adding calcium carbid thereto, allowing the mass to cool, adding benzol thereto and thickening the resulting mixture with a pulverized starchy material;

In testimony whereof I afix my signa ture.

LOGAN MALLARD. 

